1. Introduction

The bones of animals, especially vertebrates, are composed of phosphorus and calcium [hydroxyapatite] (tricalcium phosphate).

Therefore, phosphorus and calcium are essential minerals for the growth of livestock. Corn, sorghum and other feed materials contain phosphorus, but more than 60% of phosphorus exists in the form of plant enzymes. (Table-1)

Table-1 Phosphorus in feed

fodder

Phosphorus pentoxide [%]

Proportion of plant acid enzymes [%]

corn

0.27

63

kaoliang

0.26

70

tofukasu

0.62

50

Vegetable oil residue

1. 1 1

65

About 70% of organic phosphorus can be absorbed in the stomach of ruminants such as cattle, but in non-ruminants such as pigs and chickens, corn and soybeans are directly excreted because there is no plant acid enzyme.

Therefore, the simple corn sorghum compound feed is not enough to provide the phosphorus and calcium needed for bone formation. Therefore, in order to supplement calcium for ruminants and phosphorus and calcium for non-ruminants, it is considered to be very effective to use TCP feed with high solubility and easy absorption, and the ratio of phosphorus and calcium is similar to that of bone components.

2. Utilization ratio of inorganic phosphorus

The supply sources of inorganic phosphorus are as shown in Table -2, including bone meal, calcium hydrogen phosphate and defluorinated phosphate rock. There is less requirement for fluorine content, and the F/P ratio stipulated by A.A.F.C.O (American Association of Food Control Offices) should be below1100. In addition, the method to judge the effect of these products is based on β-TCP, and the chicks are fed for 4 weeks to compare and determine the bioavailability of ashes.

Table -2 Composition and Bioavailability of Experimental Feed Calcium Phosphate

Component [%]

bioavailability

comment

P

calcium (Ca)

F

Transmission Control Protocol (TCP)

18.5

30.5